A typical pen has a barrel that surrounds an ink cartridge and a cap that covers the point of the pen. When closed, the pen has an approximately cylindrical shape.
When a user finishes with the pen, it may be placed in a desk drawer or, commonly, tossed onto the top of a desk. While various stands and holders exist for pens, those tend to be large and to be pre-positioned on one part of a desk. Although movable, they are not always conveniently located when a user is finished using the pen.
When placed on a desk, a pen has little height and is easily lost among the papers and files already on the desk.